Bringing politics into music can be a dangerous game. As much as the likes of Billy Bragg and The Killing Joke have found enduring success, there is an equal risk in becoming known as a rent-a-gob, and descending into caricature.

So how do you tread the line? Jason Williamson, the front man and chief agitator for Sleaford Mods, seems to be finding a way.

As prone as his acerbic lyrics are to honing in on the establishment – “Cameron’s hairdresser got an MBE, I said to my wife, ‘You better shoot me’” – he’s equally aware that the best defence politics has is to sound, for the most part, extremely dull.

“I’m trying not to go too far on the political thing because it can become quite oppressive and there’s a danger of doing it to sound righteous,” says Williamson.

“The things that are included [in his songs] are there because they actually bother me, but to solely go down a political path is just not interesting. With all the oppression that’s going on, corrupt politics is also banal and boring, full of jargon. People don’t want that; I don’t want that.”

As their tent-bursting crowd numbers at Glastonbury last summer illustrated, Sleaford Mods are currently riding an enjoyably long wave.

Having really broken through with their 2014 record Divide and Exit, the Nottingham post-punk duo continued to thrive last year with the release of Key Markets, which reached number 11 in the UK album charts with songs including No One’s Bothered and C*** Make It Up.

Continuing the winning formula of Williamson spitting lines over the rough electronic beats of Andrew Fearn, it certainly bowled over the music press. On social media, however, Williamson admits there can be “a lot of negative feedback”.

“People just don’t get it; it goes over their heads which is brilliant, f***ing brilliant, because good music should just come

out of nowhere and surprise people. But it just really annoys me as well because it shows the lack of intelligence, it’s just quite pathetic.”

Perhaps it’s a generational issue.

Far from your average fresh-out-of-university indie band, Sleaford Mods have worked their way up the long way round. Williamson is 46, and it was only leading up to the release of his last album that he quit his job as a benefits adviser in Nottingham, having worked in previous, less successful bands for decades.

Does he think this could be why, unlike the escapist retro sounds of many bands around him, he is unwilling to stick his head in the sand?

“Yeah, I mean bands like The Last Shadow Puppets are a perfect example. Bands like Catfish and the Bottlemen, bands like Slaves; all of these bands are representative in a lot of ways – without insulting people who aren’t of similar intellect in their late 20s and early 30s – of that idiot wall of nostalgic sound.

“It’s partly their own fault and partly the fact that for decades and decades we’ve had a Tory mindset; a mindset of social mobility, of neo liberalism, mild right-wing politics that has arguably gone into extreme right-wing politics. Me and Andrew come from two or three generations before that. I’m 46 and have gone through a lot of things, so what I deem as good art is to talk about what we talk about.

“I wouldn’t entertain trying to be some kind of rock star whatsoever. I’ve lived through loads of reincarnations of that and it’s dead, it’s f***ing dead. It’s on the floor.”

When I call Williamson, I catch him in the middle of a recording stint Sleaford Mods are having down in Bristol.

Already at work on their fourth album, which is scheduled for release next year, they’re looking forward to Field Day as “one of the better festivals”.

You get the feeling Williamson won’t be going out of his way to seek much new music there, however.

As much as he’s committed in his own work to making a “scrapbook of what you see from day to day, trying to find songs from just walking down the street”, he doesn’t see such efforts from his contemporaries.

“The closest you’ve probably got to street music now in Britain is probably grime, but even that’s getting infiltrated pretty badly.

“People are trying but a lot of the time I just think there’s f***ing nothing.

“I don’t really listen to a lot of new stuff apart from East Coast rappers – lowest common denominator Mafioso rap, full of misogyny, racism, lack of self-respect and full of the ‘N Word’.

“I probably shouldn’t be listening to it but it’s the only thing that really interests me.”

Nonetheless, there should be plenty of interest for his Victoria Park appearance on June 11 – as long as you’re not David Cameron’s hairdresser.